Compare Generators Side-by-Side

Generator

Generator

6850 W

202 lbs

14.5 h

120/240

120/240

322 cc OHV 4-stroke, cast iron sleeve.

420 cc OHV 4-stroke

Recoil, Electric

Recoil, Electric

3 years

2 years

6850 W

8125 W

14.5 h

4500 W

6250 W

9.5 h

EPA, ANSI/PGMA G300-2023

CARB, EPA

840876155714

815683020067

5500

6500

4500

6250

12

9.5

60

60

OHV 4-stroke

OHV 4-stroke

cast iron sleeve

14.5

Low oil and overload protection, CO monitoring

Low oil and overload protection

Oil, funnel, tool kit, propane hose, and battery

Recoil, Electric

3

The Firman WT05571 is a 5,500-watt tri-fuel generator that runs on gasoline, propane, or natural gas. On gasoline, it delivers 6,850 starting watts and 5,500 running watts, enough to power a full home electrical panel during an outage or run multiple job site tools simultaneously. On propane, output drops to 6,250 starting and 5,000 running watts. On natural gas, it falls to 5,500 starting and 4,500 running watts. This fuel flexibility means users can switch between sources based on availability, cost, or storage preference without buying multiple generators. The tri-fuel capability makes this unit valuable for homeowners in regions with natural gas infrastructure, RV owners who can refill propane at any campground, and contractors who need to adapt to job site fuel availability. The 3 percent THD rating protects laptops, televisions, and other sensitive electronics from voltage spikes that damage circuits. At 67 decibels, the noise level sits between a typical conversation and heavy traffic, making it suitable for residential neighborhoods but audible enough that neighbors will know it is running.

The Cat RP6500 E is a 6500-watt gasoline generator built for residential backup and light commercial work. Its 8125-watt peak capacity means it can start large tools and appliances that draw high inrush current, then sustain 6500 watts of continuous power for multiple devices simultaneously. A 7.9-gallon fuel tank delivers 12 hours of runtime at 50% load, which translates to roughly one full workday or overnight backup without refueling. The gasoline engine is straightforward to maintain and refuel anywhere, making this unit practical for job sites, outdoor events, and emergency home power.